Collet chucks



Nov. 6, 1956 B. DENZLER 2,769,643

COLLET CHUCKS Filed April 276, 1954 2 Sheets-Sheet l Noir. 6, 1956 B.DENZLER 2,769,643

COLLET cHUcKs Filed April 26, 1954 2 Sheets-Sheet 2 IN V EN TOR. 35W/2af/vaf/e.

BY y? /uw gorney.

United States Patent COLLET CHUCKS Berthold Denzler, Chicago, lll.,assigner to Davos Products Co., Chicago, lll., a partnership ApplicationApril 26, 1954, Serial No. 425,385

6 Claims. (Cl. 279-50) This invention relates to improvements in chucks,particularly to a collet chuck.

One of the objects of this invention is to provide a collet chuck inwhich the collet and tool or work piece may be released and removedtherefrom and another tool or work piece and/or collet inserted andgripped while the chuck continues rotating at high speed.

Another object is to provide a collet chuck which utilizes no springs,which has a minimum number of parts, which is inexpensive to manufactureand assemble and which is highly eticient in operation.

Another object of this invention is to provide a collet chuck which isadjustable to compensate for wear and meet varied conditions ofoperation.

Other objects will become apparent as this description. progresses.

In the drawings:

Fig. 1 is an end View of my chuck.

Fig. 2 is a side View thereof.

Fig. 3 is a cross sectional view taken on line 3-3 of Fig. 1.

Fig. 4 is a cross sectional view with the parts in position for removalor insertion of the tool.

Fig. 5 is an exploded perspective view of the parts. Fig. 6 is anelevational view of the chuck attached to a motor showing the grippingand releasing positions, and Fig. 7 is a perspective View of a collet.yReferring to the drawings the numeral 10 generally designates a chuckbody having a cylindrical stem 16 provided with a shoulder 17 and areduced stem portion 18. The chuck body and stem have a tapered axialbore 12 provided with an annular shoulder 13 to receive the drivingshaft 14 of the lathe or motor 15 on which the chuck is secured. Thetapered bore may be made of any size to iit any individual smooth orthreaded shaft. The reduced stem 18 has 4 equally spaced longitudinalslots 20 each communicating at the inner ends thereof with a circularopening 22. The reduced stem 18 is tapered at the front thereof as at 24to provide a tapered nose. The stem 18 has an internal bore 21communicating with bore 12. Bore 21 forms the collet receiving socket.

The body 1G has an enlarged annular rearward portion 26 which isperipherally threaded as at 27 and which has an enlarged annular head ordisc 28 defining a shoulder portion 29. The head 28 had a pair ofopposed at portions 30 for gripping by a suitable instrument.

Supported on the body 10 is a lever ring 32 which is internally threadedas at 33 to engage the threads 27 on the portion 26. The forward portionof the lever ring 32 is provided with a pair of diametrically opposedslots 34. A pair of levers 36, each lever being received in the slot 34is pivotally mounted on pins 37 secured to the lever ring 32. The leverseach have an inverted V- shaped cutout or slot 38 which extends from theouter end to the pivot pin 37. The slotted levers provide a springaction which equalizes the pressure and compensates for wear of theparts. It also permits the collet to rmly grip tools of various sizesand tolerances. The

2,769,643 HPatented Nov. V'6, 1956 ice 2 lever 36 has a heel portion 39which is tapered outwardly and has a front upturned'mounted-terminalportion 40. The lever ring 32 has Van annular ring 'portion 42 adjacentthe front thereof which defines a shoulder 43.

Slidable axially on the stem 16-18 of the body 10 is a draw sleevegenerally indicated at 44 having an internal bore 45 which is enlargedas at 46 at the forward end thereof and which denes an annular shoulder47. The bore 46 is internally threaded at 48. The outside forward halfof the sleeve is enlarged circumferentially as at 50 to define ashoulder 53 between it and the rear outside circumferential surface 54.

The sleeve 44 has a pair of diametrically opposed longitudinal slots 56which receive the levers 36. The heels 39 of the levers engage the rearwalls 57 of the slots 56.

A clutch sleeve 60 is rotatably and axially supported on the slotteddraw sleeve 44 and said clutch sleeve has a plurality of spaced grooves62 to facilitate hand gripping. The clutch sleeve 60 has an internalannular rib 64. Secured within the forward end of clutch sleeve 60 is abushing 66 having a shoulder 67 resting against the rib 64. The forwardend of the bushing is externally threaded as at 68 to receive a threadedretaining ring 69 which locks the bushing to the clutch sleeve 60. Thebushing 66 has a circumferentially tapered rear surface 70 and anadditional circumferential tapered surface 71 adjacent thereto whichcooperates with the rounded ends of the levers 36. The taper 70 isapproximately 27 and the taper 71 is approximately a 6 taper. Thebushing forms an integral parts of the clutch sleeve 60 and is rotatablein said sleeve and is axially supported on the slotted draw sleeve 44.By providing two tapers of the character shown it is possible toaccommodate oversize and'undersize tools or work pieces in the collet.

An end cap 72 which is externally threaded at 73 is threadedly securedto the threaded portion of the draw sleeve 44. The end cap has aninternally circumferentially tapered portion 74 adapted to engage thetapered nose'24 of the stem or spindle 16-18. The cap has an annularopening 75 at the front thereof. The face of the cap has a pair ofspaced openings 76 adapted to be engaged by an adjusting wrench to bedescribed.

A lock nut or ring 77 internally threaded as at 78 threadedly engagesthe cap 72. The lock nut will be engaged by the bushing 66 when theclutch sleeve is in its forward position to limit the forward slidingmovement of the clutch sleeve. The rearward sliding movement of theclutch sleeve (FigQB) is arrested when the rear of the bushing strikesthe forward end of the ring lever 32.

At the front end of Fig. 5 is shown the adjusting wrench 80 which has apair of pins 81 for engagement with the pin holes 76 on the end cap 72.By rotating the cap clockwise as viewed in Fig. l the cap is threaded tomove inwardly with its tapered surface 74 against the nose 24 of theslotted stern 16-18 to compressV the slotted stem. By rotating thevstemcounterclockwise the cap is moved outwardly or away from the nose of thestem.

` designated by the numeral 84. The collet is inserted through theopening in the end cap and is received within the 'bore 21 of theslotted stem 18. The head 86 of the collet has a Vshoulder 87 whichengages the face of the cap to limit its rearward movement. The colletis rendered radially expansible and contractible by providing aplurality of slots 88 which extend through the head. When the collet isinserted in the stem 18 it is held in gripped position when the sleeve60 is movedV to the rear or to the right as viewed in Figs. 2 and 3 andin ungripped or released position when the sleeve is moved to the fronto'rlleft asin Fig. The sliding movement of the sleeve 60 may be effectedwhile theV chuck is rotating, thus a collet and tool may be inserted andremoved without stopping the `motorwhich is driving the chuck.

Y The operationV of the Vparts will beunderstood from Vthe'V Y.foregoing but will lbe brieily described. i

The chuck is attached to af motoror driving shaftV the lathe through thebore'12.

,In ungripping or released position the; parts ofi the Y chuck are asshown in Fig. 4. The sleeve' 60 Vhasvbeen Y. slidrto'rthe front of thechuck and'with it the tapered bushing 66,Y The frontof thepbushing willengage the.

slotted sleeve 44'forwardly or to' the left (Fig.V 4), thus theV rearWallV 57 of the slots 56 of the slotted sleeve 44 Y willstrike the heels39, ofthe ylevers 36 end cause themV to pivot upwardly andsincethetap'ered bushing 66 hasY moved forwardly the levers 36 arefree todoso. The tapered end cap 72 is then out of engagement with the taperednose' 24 of they slotted stem 18 and thus theV slotted stem 1 8 is inits `fully expanded position and capable Vof receiving the collet 84. YIn this'position the collet ring 76 and byA doingso ,will movethe end.cap 72, andV -i' on said stem, said sleeve'having .slots cooperating:with said levers, nose engaging means secured to the front of saidsleeve, a manually engageable Yclutch sleeve freely rotatable about saidbody and movable axially thereof to operate said nose engaging means onthe sleeve in relation to said tapered nose, said clutch sleeve whenmoved axially in one direction adapted to move said sleeve and causesaid nose engaging means to disengage the nose on the slotted stern andwhenfmoved in the opposite direction adapted to pivot said levers tomove said sleeve .l and cause the noseengagingrmeans to engage the noseand contract said nose. s Y Y Y t 4. A collet chuck including a bodyhaving a cylindrical slotted stem, said stem having a tapered nose and abore forming a collet receiving socket,a ring member secured to saidbody and pivotally supporting a plurality of levers, a Vslotted sleeveaxially slidable on said stem and cooperating'with said levers, atapered end cap s'eand tool may be inserted into the collet receivingborev v 21 of the stem 18 and when inserted the clutch sleeve 60 may bemoved or slid rearwardly or to the right as shown Y in Fig. 2.

When the clutchrsleeve is slid to the rear the tapered bushing 66 willpivot the levers 36` inwardly and move Ythe slotted sleeve 44rearwardly.A Since the endtcap 72 is threaded tothe sleeve 44 it moveswith it rearwardly and the tapered portion '74 ofthe endy cap engagesthenose 24 of the slotted stem and contracts same' thus holding andYlocking the collet therein against removal until the Vclutch sleeve isagain'moved'forwardly.

It willbe'understoo'd that various changesiandmodications may be made'without departing from the spirit and scope of the appended claims. Y

l claim: Y

l. A collet chuck comprisinga body having a cylindrical slotted stem,said slotted -stem'havingV a bore forming a collet receiving socket, aring member secured tosaid body and -pivotally supporting a pluralityroflevers, Ya Y 'slotted sleeve axially slidable onsaid stem with the slotsf thereof cooperating with said levers, means secured toV the front ofsaid slottedrsleeve engageable with the nose of saidtstem, amanually'engageable clutch sleeve freely rotatable on said ring'and saidslotted'sleeveand movable axially thereofY and adaptedV whenmovedforwardly to engage the meansv on Vthe front ofV said slotted sleeveandmove same away from thenose ofV said stem to permit expansion'ofsame, and said clutchsleeve Vwhen moved rearwardly adapted to pivot saidlevers to move said slotted sleeve rearwardly and cause the means on thefront of the slotted sleeve to'contra'ct said slotted stem.

Y e 2. A c ollet'chuck comprising a cylindrical stem having a colletreceiving socket, Ya ring secured; to said stem'to a slottedsleeveaxially slidable on said Ystern' with the slots` thereofcooperating with said levers, taperedV nose Y engaging means on thefront of said Vslotted Vsleeve, a

clutch sleeve freely rotatable Von said ring 'and 'slottedcured to thefront of said slotted sleeve and adapted to*Y engage said nose tocontract same, a manually engageable yclutch sleeve freely rotatableabout saidV ringV member andsaid slotted sleeve and movable axiallythereof,

said clutch sleeve adapted to cooperate with said end cap to move samein relation to Vsaidv nose, said Yclutch sleeve when moved axially inone direction adapted to move said end cap away from said nose and whenmoved in the opposite direction adapted to pivot said levers to move`said sleeve and nose engaging means so that saidV nose 'Y engaging meansengages said nose toVV contract said nose.V

pluralitytof slots to' receive said levers, a tapered endY capsecuredrtoV said sleeve to engage said tapered noseYK Vto contract'same,a manually engageable clutch sleeveV Y freely rotatable on said ring`member and VsaidY slottedV i pandable and contractibleYcolletreceivingsocket", a ringV memberV secured to'saidV bodyand'pivotally supporting aV plurality of levers, ardraw sleeve axiallyslidable on said said'stem'troV expand and contract same,'sai`d drawsleeve j 4move therewith, said ring supporting a plurality'of levers,Y Y

sleeve and movable axially thereof, said clutch' sleeve operating'saidpivoted leversfto move said slotted sleeve n Y and said end cap axiallyin relation' to said tapered nose sov that said tapered nose is inexpanded position.V

6. A collet chuck comprising a bodyY havingV a `slotted cylindricalstem, said stern Vhaving abore forming an exstem and Yhavingrneansengaging the forwardV endV of having slots Vcooperating with .saidrlevers, a-manuallyengageable sleeve freely rotatable on Vsaid ring anddraw sleeve andrmovable axially thereofY and'adapted when movedrearwardly to pivot saidV levers which move said Y draw sleeverearwardlyj to contract said colletrreceiving sleeve and axiallymovablethereon and adapted when"l Y axially moved to pivot said levers to movesaid slotted Y Y sleeve andsraid taperedvnoseengaging means so'rthatsaid Y meansiengages the'nose of said stemfto compress same'. Y 3. Acollet chuck comprising abodyV having a cylindri- VYcalY slotted stem,said stem having aV tapered nose and a bore'forming a collet receivingsocket,a plurality of levers'supported on said body, a sleeve axially;slidableV socket and when moved` forwardly to release Vsaidlsocket'Yforrexpansion. .Y v I Y Y *i References Cited the lile of Vthis* patent-KV i Y.

kUNITED sTArEsPATENTs 2,335,721 Y, 2,364,212 Hines ;"Deo Y5,'1944 12,370,729 Hoppe Marf 6,

Hines Y Oct.V 29,

Zagar Nov. 36,1- Y179.43

19,45.;VVV 1946YK

